In the Russo-Japanese War, Japan first made war with a western country. The Russian built strong fortifications at Port Arthur and the Japanese struggled to occupy it for a half year. The Japanese artillery forces consumed huge ammunition. In those days, the bombardment was inaccurate and the power of the shell was insufficient against the fortification constructions. The Japanese was much troubled with a supply of ammunition. As the production of the ammunition in Japan was not enough, Japanese imported many ammunition from western countries.

To break the deadlock of the siege, the Japanese sent 28cm Howitzers to Port Arthur. They were effective to destroy the Russian fortifications and much contributed to the occupation of Port Arthur. After the war, Japanese coastal guns were designed for the use in both coast and field.

28cm Howitzer at Port Arthur

Xiushui River

Date : March, 1939Place : Nanchang, ChinaOpponent : Chinese Army

Artillery Unit

Commander

Artillery

6th Field Heavy Artillery Brigade HQ

Major Gen. Sumita

13th Field Heavy Artillery Regiment

Lt. Col. Okoshi

24 Type 4 15cm Howitzers

14th Field Heavy Artillery Regiment

Lt. Col. Maruyama

24 Type 4 15cm Howitzers

10th Field Heavy Artillery Regiment

Lt. Col. Nagaya

24 Type 4 15cm Howitzers

15th Independent Field Heavy Artillery Regiment

Col. Horikawa

16 Type 14 10cm Cannons

2nd Independent Heavy Artillery Battalion

Lt. Col. Manba

4 Type 89 15cm Cannons

101st Field Artillery Regiment

Lt. Col. Yamada

34 Type 38-improved 75mm Field Guns

3rd Independent Mountain Gun Regiment

Lt. Col. Morikawa

24 Type 41 75mm Mountain Guns

106th Field Artillery Regiment

Lt. Col. Uga

32 Type 38-improved 75mm Field Guns

2nd Battalion/2nd Independent Mountain Gun Regiment

Major Matsumoto

12 Type 41 75mm Mountain Guns

During the Sino-Japanese War, Japanese artillery forces marched a long distance in the vast China Continent and they were much troubled with bad roads in China. To lighten the burden to transport the artillery, many artillery regiments replaced their artillery with mountain guns.

Most fights in China were the pursuit battle and the large artillery battle seldom happened. In the Battle of Nanchang, the Japanese deployed the largest artillery forces during the Sino-Japanese War. They bombarded to support the river-crossing of the Japanese at Xiushui River. However, the Chinese little resisted the Japanese river-crossing and the artillery forces stopped bombarding at one third of the plan.

In the Nomonhan Incident, Japanese artillery forces made an artillery duel against the Soviet. The result was the defeat of the Japanese. Japanese artillery were outranged by the Soviet artillery and the terrain was disadvantagous to the Japanese. However, the most problem was the supply of ammunition again. Japanese artillery forces had used up most of the piled ammunition in three days and they could not continue an artillery duel any more. On the contrary, Soviet artillery continued the heavy bombardment with an abundant supply of ammunition and defeated Japanese artillery.

In the war against the China, the Japanese did not experience large artillery battle. They had forgotten the lesson of the Port Authur. The result of the Nomonhan battle revealed the problems of Japanese artillery forces. However, while they were not improved, Japan was driving to the war in the Pacific.

Type 38 12cm Howitzer of 13th Field Artillery Regiment at Nomonhan

Bataan and Corregidor

Date : Jan. - May, 1942Place : The PhilippinesOpponent : US Army

Artillery Unit

Commander

Artillery

4th Field Gun Regiment

Col. Inoue

16 Type 38-improved 75mm Field Guns8 Type 91 10cm Howitzers

22nd Field Gun Regiment

Col. Itoh

24 Type 38-improved 75mm Field Guns12 Type 91 10cm Howitzers

Field Gun Batteries/65th Brigade

12 Type 38 75mm Field Guns

3rd Battalion/51st Mountain Gun Regiment

Major Arima

12 Type 41 75mm Mountain Guns

1st Artillery HQ

Major Gen. Kitajima

1st Field Heavy Artillery Regiment

Col. Irie

24 Type 96 15cm Howitzers

8th Field Heavy Artillery Regiment

Lt. Col. Takahashi

16 Type 92 10cm Cannons

3rd Independent Mountain Gun Regiment

Lt. Col. Takamori

24 Type 41 75mm Mountain Guns

1st Heavy Artillery Regiment

Col. Hayakawa

8 Type 45 24cm Howitzers

9th Independent Heavy Artillery Battalion

Lt. Col. Sugai

8 Type 89 15cm Cannons

2nd Independent Heavy Artillery Company

Captain Shinoda

2 Type 96 15cm Cannons2 Type 96 24cm Howitzers

2nd Independent Mortar Battalion

Lt. Col. Namimatsu

12 15cm Mortars

14th Independent Mortar Battalion

Major Tanaka

16 Type 98 32cm Spigot Mortars

15th Independent Mortar Battalion

Lt. Col. Yoshida

8 Type 98 32cm Spigot Mortars

After the failure of the first attack against the Bataan, the Japanese GHQ sent strong artillery forces to the Philippines in order to smash the American fortifications. They had 190 guns and included some big guns like 15cm cannons or 24cm howitzers. Especially, Type 96 24cm Howitzer was a very rare gun and its action is only known in this battle. To command and control these artillery forces, the 1st Artillery HQ also moved to the Philippines. The HQ commander was Major Gen. Kineo Kitajima, who was a leader and authority of the IJA artillery.

On April 3rd, about 300 guns bombarded the enemy positions. It started from 9:00 and continued to 15:00. Synchronized with bombardment, about 100 airplanes dropped more than 700 bombs. The land shaked and the mountains were covered with the dust of explosion. It was just like a volcano erupted. When the Japanese troops started the attack at 15:00, there was a little resistance. American defenders, shocked by heavy bombardment were routed. The Bataan Peninsula was occupied only in one week.

The consumption of the shells during the battle of Bataan is as follows.

In the battle of Corregidor, heavy artillery were used to destroy the batteries on the fortress islands. The Type 96 15cm Cannon first saw action at this time. They bombarded the Corregidor and two islands for about one month and silenced most enemy batteries. On May 5th, Japanese ground forces landed the Corregidor Island and the garrisons surrendered the next day.

The consumption of the shells during the battle of Corregidor is as follows.

For the October offensive, the Japanese sent some artillery units to Guadalcanal. Sending artillery were almost landed on Guadalcanal, but ammunition were many lost by enemy airraid. During the October offensive, most artillery units were attached to the Sumiyoshi Detachment and deployed in the west bank of the Matanikau River. The ammunition of these units were very few as shown below.

Due to the shortage of the ammunition, the bombardment of Japanese artillery was limited. They could only disturb the enemy. Moreover, once a Japanese artillery fired, the Americans heavily counterattacked it by air and artillery. For fear of American counterattack, Japanese artillery men became to hesitate to fire.

When the Japanese evacuated Guadalcanal, one 15cm howitzer continued to fire to the end in order to camouflage the Japanese evacuation. It was the last artillery of the Japanese on Guadalcanal.

Despite the heavy bombardment and bombing of the Americans prior to the landing, Japanese artillery were not so damaged because they were well camouflaged. When landing crafts approached the beach, Japanese artillery opened fire and damaged several crafts. Especially, Japanese 15cm Howitzers bombarded the landing beach heavily and shocked American soldiers. The Americans landed their guns and coped with Japanese artillery. By furious artillery duel, about a half of Japanese artillery were destroyed until the evening.

At the night of 16th day, the Japanese made a large counterattack. Japanese artillery supported it and bombarded enemy artillery positions. Japanese infantymen and tanks rushed to the enemy. However, they were replused by the Americans and suffered heavy losses. Japanese artillery were mostly destroyed until the evening of 17th day.

The Japanese garrisons built strong fortifications on Iwo Jima. Artillery were hidden in cave or pillbox and well protected from the bombardment and airraid. In the underground magazines, they had stocked about 60% of the standard ammunition for one campaign. Except for naval guns, there were no heavy artillery. But, they had received some rocket artillery. They were 20cm or 40cm caliber, which are equal to the gun of warship.

The Americans landed on Iwo Jima suffered serious damage by Japanese shellfires. Japanese artillery endured for a long-time fight and supported the resistance of the garrisons. They devoted themselves to the bombardment by surprise and never made an artillery duel. Field guns ambushed and destroyed enemy tanks.

During the battle of Iwo Jima, Americans suffered 6,800 killed and more than 19,000 wounded. Most of them were caused by the bombardment of artillery and mortar. In the 4th Marine Division, for example, 75% of the casualties were due to the bombardment. Japanese artillery forces on Iwo Jima had accomplished their duty.

Kotou Fortress located near Ussuri River in the Soviet-Manchurian border (See map). It was the strongest fortress among eight Japanese fortresses in Manchuria and the 4th Border Guard Unit guarded it. The 4th Border Guard Unit had following artillery unit. 41cm Howitzer was the largest gun of the IJA and Type 90 24cm Railway Gun was only one railway gun of the IJA.

As the Japanese declined in the Pacific theater, many soldiers and guns were extracted from the Kotou Fortress and sent to the Pacific. In 1945, the 4th Border Guard Unit was disbanded and the 15th Border Guard Unit was formed in July, 1945 as the garrison unit of the Kotou Fortress.

When the Soviets invaded Manchuria in Aug., 1945, there were about 1,400 garrisons at the fortress. The 41cm gun fired and destroyed a railway bridge of the Trans-Siberian Railroad. Then, it fired with over 100 rounds during about one week until it was overrun by Soviet infantry.

Though the Soviets announced the surrender of Japan, Japanese garrisons did not believe it. They continued to fight until they were annihilated. The battle of Kotou Fortress ended on Aug. 26th.